Sodium hypochlorite

Genetic toxicity: in vivo

Administrative data

Endpoint:

in vivo mammalian somatic cell study: cytogenicity / erythrocyte micronucleus

Remarks:

Type of genotoxicity: chromosome aberration

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: No deficiencies.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1988

Materials and methods

Test guideline

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 474 (Mammalian Erythrocyte Micronucleus Test)

Deviations:

no

GLP compliance:

no

Type of assay:

micronucleus assay

Test material

Test material information

Constituent 1

Reference substance name:

Sodium hypochlorite

EC Number:

231-668-3

EC Name:

Sodium hypochlorite

Cas Number:

7681-52-9

Molecular formula:

ClO.Na

IUPAC Name:

sodium hypochlorite

Details on test material:

Sodium hypochlorite
content (as Cl-): 6.6 %

Test animals

Species:

mouse

Strain:

other: ddY

Sex:

male

Details on test animals or test system and environmental conditions:

Source: Shizuoka Agricultural Cooperative Association for Laboratory Animals, Shizuoka, Japan)
8 weeks old
weight not stated

Administration / exposure

Route of administration:

intraperitoneal

Vehicle:

Saline

Details on exposure:

Number of applications: 1 and 4

Duration of treatment / exposure:

single injection

Frequency of treatment:

Interval between applications: 24 hours

Post exposure period:

24 hours

Doses / concentrations

Doses / concentrations 1

Remarks:

Doses / Concentrations:
312.5, 625, 1250 or 2500 mg/kg bw
Basis:
nominal conc.
sigle dose test

Doses / concentrations 2

Remarks:

Doses / Concentrations:
300 mg/kg bw
Basis:
nominal conc.
four-doses test

No. of animals per sex per dose:

6

Control animals:

yes, concurrent vehicle

Examinations

Tissues and cell types examined:

Clinical signs: No
Tissue : Bone marrow

Details of tissue and slide preparation:

Number of animals: all animals
Number of cells: 1000
Time points: 24 hours
Type of cells: erythrocytes
Parameters: micronucleated polychromatic erythrocytes, polychromatic/total erythrocytes ratio

Results and discussion

Test results

Sex:

male

Genotoxicity:

negative

Toxicity:

no effects

Vehicle controls validity:

valid

Negative controls validity:

valid

Positive controls validity:

valid

Additional information on results:

There was no sign of genotoxicity under the conditions described in the study.

Any other information on results incl. tables

Results of the micronucleus test with sodium hypochlorite in mice

Dose	MNPCE [%]	PCE [%]	Mortalities
0	0.17 ± 0.16	56.7 ± 14.8	0/6
312.5	0.20 ± 0.09	61.3 ± 3.8	0/6
625	0.22 ± 0.20	56.2 ± 9.8	0/6
1250	0.17 ± 0.08	29.3 ± 11.8	0/6
2500	-^a	-	6/6
positive control^b	3.77 ± 1.08	47.7 ± 18.9	0/6
300^c	0.17 ± 0.12	47.3 ± 9.8	0/6

MNPCE              micronucleated polychromatic erythrocytes

PCE                     polychromatic erythrocytes

a                           Not evaluated due to mortalities

b                           2.0 mg/kg bw Mitomycin C

c                           4 doses of 300 mg/kg bw each, 24 hours spacing

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): negative
There was no sign of genotoxicity under the conditions described in the study. For details please refer to Table.

Executive summary:

Groups of eight weeks old, male ddY mice were intraperitoneally administered a single dose of sodium hypochlorite at concentrations of 0, 312.5, 625, 1250, 2500 mg/kg bw in a first test run. In a second trial 4 doses of 300 mg/kg bw spaced by 24 hours were similarly administered. The animals were killed by cervical dislocation 24 hours after the (last) administration. Femoral marrow cells were flushed out with foetal bovine serum and smeared on clean glass slides. Cells were fixed and stained with Giemsa. 1000 polychromatic erythrocytes were scored using a light microscope and the number of micronucleated polychromatic erythrocytes was recorded. The proportion of polychromatic erythrocytes among the total erythrocytes was also evaluated by observing 1000 erythrocytes on the same slide.

There was no sign of genotoxicity under the conditions described in the study. For details please refer to Table.